Trading on the LME floor is conducted by open outcry and is supported by a 24-hour inter-office market and through the LME's electronic trading platform - LME Select. A typical day for a broker member might begin at 07.00 with a team of traders and support staff operating from their offices in order to service the Far Eastern time zone. The categories of members empowered to write client contracts are able to do so at any time â such activity is not restricted to the periods of floor trading.

From around 07.00 (London Time) throughout the morning, traders will make markets, for the purchase and sale of metal to producers, consumers and other trading companies who are seeking to lay off risk. This is done either by telephone or e-commerce from office to office.

At 11.45, dealing teams from the ring dealing members assemble at the Exchange and the first session of open outcry trading ("the ring") begins. Each contract trades in turn for a five-minute period. At 12.20, when all eight metal contracts have traded once, there is a ten-minute break before, starting at 12.30, each contract again trades for five minutes.

The second floor trading period is, in many ways, the focal point of the day, since it gives rise to the settlement and official prices. At around 13.15, once the official pricing is complete, a period of trading known as the "kerb" begins.

The name "kerb" is derived from the practice of members in the early part of this century to gather on the roadside after the morning session and to continue to trade. Today, this less formal trading session takes place in the ring and lasts until 15.10, during which time all eight contracts and LMEX, the index contract, trade simultaneously.

Floor trading in LMEX is, in fact, only carried out during kerb sessions. It does not have its own individual five minute calls.

The morning floor trading session ends at the close of the kerb and trading moves back to the inter-office arena. However, it should be realised that inter-office trading does not cease during ring times. It is simply that the focus of trading is changed.

The second floor trading session begins at 15.10, and follows the structure of the first session, ending with a kerb trading period of 25 minutes from 16.35 until 17.00. The important difference between morning and afternoon sessions, is the fact that no official prices are announced in the afternoon. From 17.00, the market reverts to inter-office trading.